Phantom Voltage

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LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
All readings go away when the lamp is connected or when a wiggy is connected or when I physically connect with my fingers across the de-energized hot to neutral or de-energized hot to ground.
Why wouldn't he be willing to accept his readings as accurate with the circuit "loaded" with a lamp?
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
The first time I became aware of phantom voltages was using a Simpson analog. The method I used at that time was to change scales. Starting at the highest setting the meter would read 1/4 scale up. Changing scales to the next and subsequent lower scales would result in the meter reading at about the same 1/4 scale up. Has to do with the ohms per volt on each scale.
 

brian john

Senior Member
Location
Leesburg, VA
IN defense of the inspector, he ran into a situation he was not sure how to handle, the EC could not answer his questions and they were equally concerned the PQ guy from the local POCO was not sure and washed his hands of any responsibility in writing (which was correct).

I tried from a 12.00 dollar bug-eye to a 5,000.00 dollar Fluke and had the same results. The one issue that baffled me was I did not figure the Simpson or Ideal bug-eye to indicate voltage.

What is the correct terminology for the bug-eye?
 

iaov

Senior Member
Location
Rhinelander WI
Phantom voltages are why I would never leave home without my VolCom Wiggy. My Fluke 87 is a wonderfull tool but my Wiggy is my "reality checker".:smile:
 

wptski

Senior Member
Location
Warren, MI
Test.

50' 12-3 extension cord Black conductor connected to 20 amp CB at 120 VAC, Neutral connected to ground conductor termination bar in panel. Ground not terminated on either end. Prior to the test the extension cord was meggered black to white 18.2 gig, black to green 22.3 Gig white to green 19.1 Gig for one minute each at 1000 VDC

Hot to neutral (black to white)

Fluke 87 121.7 VAC
Simpson 120 VAC

Hot to green

Fluke 87 58.8 VAC
Simpson 60 VAC

Neutral to green

Fluke 87 58.61 VAC
Simpson 60 VAC

Ground Green conductor

Fluke 87 68.06 millivolts
Simpson 0 volts


need to get to HD or Lowe's for a Ideal tester. I assume they will have one of these?
If your using a three wire extension cord here, what/where are you measuring in that last listed measurement?:confused:
 

gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
090207-1608 EST

Obviously in my post numbered #20 I should have said 5 megohms, and not 5,000,000 megohms for the Simpson DC input resistance.

.
 

gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
090207-2230 EST

brian john:

Your description is still vague. Having grounded green (the EGC), then what was the voltage measured between?

.
 

wptski

Senior Member
Location
Warren, MI
090207-2230 EST

brian john:

Your description is still vague. Having grounded green (the EGC), then what was the voltage measured between?

.
gar:

If the green was grounded then such a low voltage would look like it was between the neutral and green wire.

Funny, I believe I used a Ideal Suretest 61-165 on a circuit wired this way some time ago. I think that it just showed it as being dead till I discovered that it was switch controled.

I returned my Suretest for that AFCI upgrade so I can't double check that right now!:rolleyes:
 
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wptski

Senior Member
Location
Warren, MI
In the last measurement I grounded the green conductor my description was somewhat vague Sorry.




Is that the Ideal Vol-Con?
The neon light that flickers or whatever on the Ideal tester is what fault failure? I tried looking at pictures of it but couldn't read the writing.
 

wptski

Senior Member
Location
Warren, MI
Not sure what you are asking?
In a post above you stated: The Ideal 61-501 does light up (middle yellow) on phantom voltage

The tester has a chart printed on its sticker showing what each sequence of lights ON/OFF means. If the middle yellow light is ON, what does it say that it means?
 

brian john

Senior Member
Location
Leesburg, VA
In this instance it really does not matter to me (unless it says the middle light partial illuminated is a false reading) I left the bug eye in the office and will post what it says on Monday unless someone wants to go to their truck and get one.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
The tester has a chart printed on its sticker showing what each sequence of lights ON/OFF means. If the middle yellow light is ON, what does it say that it means?
This is one reason I don't like combination testers. I want a wiggy, I want a voltmeter, and I want a continuity tester. Three separate instruments.

Kind of like my cellular phone. I want it for making and receiving phone calls. I have a camera for photographs and a video camera for motion video.

The wiggy won't do anything without external power, so it won't indicate anything else.


(Actually, the phone and camera both do photos and video, but that's beside the point.)
 

wptski

Senior Member
Location
Warren, MI
This is one reason I don't like combination testers. I want a wiggy, I want a voltmeter, and I want a continuity tester. Three separate instruments.

Kind of like my cellular phone. I want it for making and receiving phone calls. I have a camera for photographs and a video camera for motion video.

The wiggy won't do anything without external power, so it won't indicate anything else.


(Actually, the phone and camera both do photos and video, but that's beside the point.)
I'm just curious as to what fault it's showing.
 

brian john

Senior Member
Location
Leesburg, VA
I'm just curious as to what fault it's showing.



Center yellow light indicates open ground. The center yellow light is dim and flickering.

From the Ideal web site.
Note item two.

1. All appliances or equipment on the circuit being tested should be unplugged to
help avoid erroneous readings.
2. Not a comprehensive diagnostic instrument but a simple instrument to detect
nearly all common improper wiring conditions.
3. Refer all indicated problems to a qualified electrician.
4. Will not indicate quality of ground.
5. Will not detect two hot wires in a circuit.
6. Will not detect a combination of defects.
 

quogueelectric

Senior Member
Location
new york
090207-0726 EST

quo:

The Simpson is 20,000 ohms/volt on DC (a 50 microamp meter movement), and on AC it is 5,000 ohms/volt.

At the 250 range this translates to 5,000,000 megs DC, and 1.25 megs on AC.

An interesting aside. The other night I compared two Simpson 270 meters with my Fluke 27 on DC and the microamp range. One Simpson is 1961 and the other is later 60s. The 1961 is pivot and jewel, and the other is taut band. All three were within 1/2% at 50 microamps. The 1961 had a slight offset in mid range, otherwise all tracked very well.

My 1947 Simpson 260 reads 100 microamps with 98 as the input. This is still a 20,000 ohms/volt meter, but there was no 50 microamp input selection.

What is amazing is that the meter magnets have been so stable.

.

Simpson was the cats MEOW 30 yrs ago. When I was in school for electronics my professor was trying to sell the intel company to anyone in the class that would buy it as it was up for sale. Motorola was giving free educational info to the universities so that students would train on motorola products and be more familiar with them when they got in the field. It didnt quite work out that way. I wish I had an extra million or two to buy intel back then.
 
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